I cannot view my hdd

I have also checked Disk Management and the HDD is not visible there either.

Hello,

Give us as much info as you can about your laptop, make, model #, HDD, and the same for your removable drive. Is this drive powered by the USB cable or separate power block? If it has the choice to use an ext power supply, use that.

First thing to do is run a thorough virus scan to make sure this is not virus or malware related.

Then with removable drive attached, go to disk management, and select the removable drive, and uninstall it thru the context menu.
Then reboot and with the removable drive attached, let Windows 'find new hardware' and install the proper driver. If it's a driver problem that may correct it, if its a corrupted partition on the removable drive, it won't help but won't hurt.

My laptop is a compaq presario cq60 and the hard drive is a trekstor datastation maxi g.u. I have tried everything you have suggested and when the drive was reinstalled it states it is ready to use but is still not showing up in My Computer. In Disk Management it says the driver is not initialised but when I try to do this I get an error message saying it is an incorrect function; however in Properties it states the driver is working properly.

The fact that it is seen in Device Manager means the OS recognizes the drive and the drive itself is probably OK.
The not initialized means there is no disk signature on the removable drive, which is incorporated in the Partition information in the MBR.

Do you have important data on this drive or not? Could you repartition and reformat the drive without much of a loss?

The next step is to use a Partition management program, to attempt to reestablish the Drive signature, or reestablish the Disk Partition.
Download and run the Easeus Partition Master free edition, to see if it can reestablish the Partition Information that may be corrupted. Here is the link.

Partition Manager, Disk & Partition Copy Wizard, Partition Recovery Wizard.

www.partition-tool.com/personal.htm

I use my drive as my main storage unit so all my photos, music and videos are stored on it. I would not be able to replace a lot of these documents. If I do as you suggest, will it wipe my drive?

Use should try the Easeus Partition Master to see if it can reestablish the partition information so you can access all your important files. It will not do anything destructive to the data on the drive.

If that is not successful, then you will need to use a data recovery program, that finds recognized file types on this drive, and moves them to a clean properly functioning HDD. To do that, you will need a separate clean partitioned and formatted HDD at least the size of this drive so that your data can be copeid over to it.

Try the Partition Master first.

I'll try that - thatnk you very much

I am trying to run Partition Manager on my external hard drive but I cannot view it on the disk list. What should I do?

If you can't see the partition on the removable hard drive, then you should use the Easeus Data Recovery Wizard. I am assuming it's still true you can see this drive in the Device Manager.

Here is the link
www.easeus.com/datarecoverywizard/

It can in many cases scan the drive, and repair the corrupted partition or redo the disk signature. Hopefully that will work.
If not, then you will need to use the "Data Recovery" part of that program to move your data to a functional HDD, as mentioned before.
The Data Recovery Wizard will recover 1 GB of data free, more than that you are requried to purchase the commercial version for $69.95.
Another option would be the Acronis Disk Director which is also commercial and very well regarded.

I already tried the data recovery and even though it recognises the drive, it is stating there are no files to select

These findings are not encouraging. It may well be that your files are not going to be recoverable.

Here is another fairly powerful data recovery application that is free and worth trying.

"Test Disk" by CGSecurity "Christophe​ Grenier". It was primarily designed to help recover lost partitions and/or make non-booting disks bootable again.

Here is the link to this program http://www.cgsecurity.org/wiki/TestDisk